Fluid delivery device

ABSTRACT

A fluid delivery device comprises a housing having a fluid reservoir. A needle is in fluid communication with the fluid reservoir in an engaged position and out of fluid communication with the fluid reservoir in armed and storage positions. A proximal end of a biasing member is coupled to the housing and a distal end of the biasing member is configured to deliver a force to the fluid reservoir. A piston member extends through the biasing member and is coupled to the distal end of the biasing member. The piston member is fixed with respect to the housing in a locked position such that the biasing member does not deliver the force to the fluid reservoir and moveable with respect to the housing in a released position such that the biasing member delivers the force to the fluid reservoir. Transitioning the needle from the storage position to the armed position transitions the piston from the locked position to the released position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/500,136, filed on Oct. 12, 2010, which is a National Stage PatentApplication of International Patent Application No. PCT/US2010/052352filed on Oct. 12, 2010, which claims the benefit of U.S. ProvisionalPatent Application No. 61/251,236 filed on Oct. 13, 2009 entitled “FluidDelivery Device”, and U.S. Provisional Patent Application No. 61/325,136filed Apr. 16, 2010 entitled “Fluid Delivery Device” all of which areincorporated by reference herein in their entirety.

BACKGROUND OF THE INVENTION

The present invention generally relates to a fluid delivery device andmore particularly to an ambulatory device for delivering a medicament toa patient.

Many attempts have been made to provide dosing of drugs and otherfluids, such as insulin, using ambulatory pump systems. Although somesystems for continuous delivery work quite well, individuals using thesesystems, particularly in continuous dose mode, need to monitor thedevices closely to ensure continuity and accuracy of dosing undervariable environmental conditions such as temperature and air pressure.In addition, there are few options for individuals who require theability to vary the dose of medication quickly and accurately, and mostof the available options are cumbersome, difficult to operate,intrusive, and/or expensive.

Accordingly, it would be desirable to provide a simple, intuitive,inexpensive ambulatory device able to provide fluid dosing under patientcontrol, as well as safety and consistency in the metered and/orcontinuous dose over a wide range of environmental conditions.

BRIEF SUMMARY OF THE INVENTION

In one embodiment there is a fluid delivery device that comprises ahousing having a fluid reservoir. A needle has a storage position, anarmed position, and an engaged position. The needle is in fluidcommunication with the fluid reservoir in the engaged position and outof fluid communication with the fluid reservoir in the armed and storagepositions. A biasing member has a proximal end and a distal end. Theproximal end of the biasing member is coupled to the housing and thedistal end of the biasing member is configured to deliver a force to thefluid reservoir. A piston member extends through the biasing member andis coupled to the distal end of the biasing member. The piston member isfixed with respect to the housing in a locked position such that thebiasing member does not deliver the force to the fluid reservoir and ismoveable with respect to the housing in a released position such thatthe biasing member delivers the force to the fluid reservoir.Transitioning the needle from the storage position to the armed positiontransitions the piston from the locked position to the releasedposition.

In a further embodiment, the fluid delivery device comprises a hydraulicbasal chamber coupled between the biasing member and the fluidreservoir. In a further embodiment, the fluid delivery device comprisesa hydraulic pump chamber and a flow restrictor fluidly coupling thehydraulic pump chamber and the hydraulic basal chamber. In oneembodiment, the piston includes a plunger tip coupled to the hydraulicbasal chamber. In one embodiment, the piston is releaseably coupled tothe housing with a pin extending through the housing and a cap extendsover the needle in the storage position, the cap being coupled to thepin such that removing the cap releases the piston. In one embodiment,the biasing member comprises at least two overlapping coaxial springs.

In another embodiment, a fluid delivery device comprises a housinghaving a fluid reservoir. A first biasing member is coupled to thehousing. A second biasing member is coupled to the first biasing memberin series and at least partially overlapping the first biasing member.The first and second biasing members are configured to deliver a forceto the fluid reservoir. In a further embodiment, the fluid deliverydevice comprises a plunger extending through the first and secondbiasing members. In one embodiment, the plunger is coupled to the secondbiasing member at a distal end and is releaseably coupled to the housingat a proximal end. In one embodiment, the plunger is releaseably coupledto the housing with a pin extending through the housing and the plunger.In one embodiment, the plunger is releaseably coupled to the housingwith a pin extending through the housing and further comprising a needlecover coupled to the pin.

In a further embodiment, the fluid delivery device comprises a hydraulicbasal chamber coupled between the first and second biasing members andthe hydraulic pump chamber and a flow restrictor fluidly coupling thehydraulic basal chamber and the hydraulic pump chamber. In oneembodiment, the hydraulic pump chamber has a cross sectional area lessthan the cross sectional area of the hydraulic basal chamber. In afurther embodiment, the fluid delivery device comprises a sleevecoupling the first biasing member with the second biasing member. Thesleeve has a length generally equal to the length of overlap between thefirst and second biasing members. In one embodiment, the sleeve has abody, a first flanged end and a second flanged end, the first flangedend extending radially outwardly from the body of the sleeve andconfigured to couple with an end of the first biasing member, and thesecond flanged end extending radially inwardly from the body andconfigured to couple with an end of the second biasing member.

In another embodiment, a fluid delivery device comprises an attachmentsurface configured to engage with a skin surface and having a firstthermal conductance and a hydraulic pump chamber. A hydraulic basalchamber has a portion of the outer wall proximate the attachment surfaceand having a second thermal conductance. The second thermal conductanceis greater than the first thermal conductance. A flow restrictor isfluidly coupling the hydraulic basal chamber and the hydraulic pumpchamber. A fluid reservoir is coupled to the hydraulic pump chamber. Thefluid reservoir is configured to contain a fluid deliverable to apatient. An actuator is coupled to the hydraulic basal chamber. Theactuator is configured to pressurize the hydraulic pump chamber totransfer energy through the hydraulic basal chamber and the hydraulicpump chamber to the fluid reservoir to deliver the fluid at a sustainedbasal rate. In one embodiment, the attachment surface includes aninsulating member.

In one embodiment, the insulating member is at least partially relievedto at least partially expose the portion of the outer wall of thehydraulic basal chamber proximate the attachment surface. In oneembodiment, the fluid reservoir is at least partially spaced from thehousing. In a further embodiment, the fluid delivery device comprises ahousing having a bottom surface. The outer wall portion of the hydraulicbasal chamber extends outwardly from the bottom surface of the housing.In one embodiment, the portion of the outer wall of the hydraulic basalchamber has an imaginary tangent generally aligned with the attachmentsurface. In one embodiment, the portion of the outer wall of thehydraulic basal chamber is configured to directly contact the skinsurface. In one embodiment, a remainder of the outer wall of thehydraulic basal chamber has a third thermal conductance. The thirdthermal conductance being less than the second thermal conductance.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The foregoing summary, as well as the following detailed description ofembodiments of the fluid delivery device will be better understood whenread in conjunction with the appended drawings of an exemplaryembodiment. It should be understood, however, that the invention is notlimited to the precise arrangements and instrumentalities shown.

In the drawings:

FIG. 1 is a perspective view a fluid delivery device in accordance withan exemplary embodiment of the present invention;

FIG. 2 is an exploded perspective view of the fluid delivery deviceshown in FIG. 1;

FIG. 3 is a schematic top, cross sectional view of a fluid deliverydevice in accordance with an exemplary embodiment of the presentinvention;

FIG. 4A is a top cross sectional view of the fluid delivery device shownin FIG. 1 taken along line 4A-4A of FIG. 1;

FIG. 4B is a top partial cross sectional view of the fluid deliverydevice shown in FIG. 1 taken along a length of a flow restrictor;

FIG. 5 is a front cross sectional view of the fluid delivery deviceshown in FIG. 1 taken along line 5-5 of FIG. 1;

FIG. 6A is a side cross sectional view of a basal hydraulic chamber andbiasing members of the fluid delivery device shown in FIG. 1 taken alongline 6A-6A of FIG. 1 show in an initial position;

FIG. 6B is the side cross sectional view of FIG. 6A shown in the engagedposition;

FIG. 6C is the side cross sectional view of FIG. 6A shown in the engagedposition after a length of time in use;

FIG. 7 includes side cross sectional views of first and second biasingmembers of the fluid delivery Device shown in FIG. 1 in comparison withside cross sectional views of a conventional single biasing member;

FIG. 8 is a side cross sectional view of a bolus button and a bolushydraulic chamber of the fluid delivery device shown in FIG. 1 takenalong line 8-8 in FIG. 1;

FIG. 9A is an illustrative perspective view of the fluid delivery deviceshown in FIG. 1 in the engaged position on a user and showing the userunlocking a bolus button;

FIG. 9B is an illustrative perspective view of the fluid delivery deviceshown in FIG. 1 in the engaged position on the user and showing the userpressing the bolus button;

FIG. 10A is a partial, top, cross sectional view of the fluid deliverydevice shown in FIG. 1 taken along line 4A-4A with the bolus button inan initial locked position;

FIG. 10B is a partial, front, cross sectional view of the fluid deliverydevice shown in FIG. 10A taken along line 10B-10B;

FIG. 11A is a partial, top, cross sectional view of the fluid deliverydevice shown in FIG. 1 taken along line 4A-4A with the bolus button inthe released position;

FIG. 11B is a partial, front, cross sectional view of the fluid deliverydevice shown in FIG. 11A taken along line 11B-11B;

FIG. 12A is a partial, top, cross sectional view of the fluid deliverydevice shown in FIG. 1 taken along line 4A-4A with the bolus button in alocked position after delivery a bolus dose;

FIG. 12B is a partial, front, cross sectional view of the fluid deliverydevice shown in FIG. 12A taken along line 12B-12B;

FIG. 13A is a partial, top, cross sectional view of the fluid deliverydevice shown in FIG. 1 taken along line 4A-4A with the bolus button inthe locked position and a release button in a locked position andindicating that the bolus button has been completely deployed;

FIG. 13B is a partial, front, cross sectional view of the fluid deliverydevice shown in FIG. 13A taken along line 13B-13B;

FIG. 14 is a side cross sectional view of a pump chamber, medicinalpiston and a fluid reservoir of the fluid delivery device shown in FIG.1 taken along line 14-14;

FIG. 15 is an enlarged side cross sectional view of the medicinal pistonshown in FIG. 14;

FIG. 16A is a perspective view of the fluid delivery device shown inFIG. 1 in an initial or storage position;

FIG. 16B is a perspective view of the fluid delivery device shown inFIG. 1 with the button cap removed and the biasing members engaged;

FIG. 16C is a perspective view of the fluid delivery device shown inFIG. 1 in the engaged position;

FIG. 17 is a front cross sectional view of the fluid delivery deviceshown in FIG. 16A taken along line 17-17;

FIG. 18 is a front cross sectional view of the fluid delivery deviceshown in FIG. 16C taken along line 18-18;

FIG. 19 is an enlarged front cross sectional view of a portion of aneedle with a needle cap shown in FIG. 18;

FIG. 20 is a partially exploded cut away view of a lock out assembly ofthe fluid delivery device of FIG. 1;

FIG. 21 is a top, partially cut away view of a lock out assembly of thefluid delivery device of FIG. 1 in an initial or ready to be engagedposition;

FIG. 22 is a top, partially cut away view of a lock out assembly of thefluid delivery device shown in FIG. 1 in a locked out position;

FIG. 23A is a partial bottom plan view of the fluid delivery device ofFIG. 1 with the adhesive patch removed showing a lock button in aninitial position;

FIG. 23B is a partial bottom plan view of the fluid delivery deviceshown in FIG. 23A with the lock button moved in a first direction; and

FIG. 23C is a partial bottom plan view of the fluid delivery deviceshown in FIG. 23A with the lock button moved in first and seconddirections.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings in detail, wherein like reference numeralsindicate like elements throughout, there is shown in FIGS. 1-23C a fluiddelivery device, generally designated 110, in accordance with anexemplary embodiment of the present invention. The fluid delivery device110 may include one or more features described herein which facilitateor improve accurate delivery of a fluid and ease of use by a user orpatient. The benefits provided by these features translate readily toimproved patient compliance and improved therapeutic outcome.

In one embodiment, the fluid delivery device 110 is a discreteambulatory insulin delivery pump. The fluid delivery device 110 may besingle use, disposable and incapable of reuse. In preferred embodiments,the fluid delivery device 110 is completely mechanical and hydraulic andhas no electronic components or aspects. The fluid delivery device 110may provide excellent therapeutic capability in a small, single use,disposable package and can be produced using high volume manufacturingfabrication (e.g., injection molding) and assembly processes, allowingfor low cost-of goods. Devices of the invention can be used for a broadrange of applications, including, but not limited to, clinicalapplications (administration of medicaments, etc.) and biomedicalresearch (e.g., microinjection into cells, nuclear or organelletransplantation, isolation of single cells or hybridomas, etc.).

In one embodiment, the fluid delivery device 110 is a device fordispensing, delivering, or administering the fluid or agent to the useror patient. The fluid may be any therapeutic agent. In one embodiment,the fluid is a low viscosity gel agent. In one embodiment, the fluid isan analgesic agent. In one embodiment, the fluid is insulin. In oneembodiment, the fluid is a U100 insulin. In another embodiment the fluidis a U200 insulin. In another embodiment the fluid is a U300 insulin. Inanother embodiment, the fluid is a U500 insulin. In another embodimentthe fluid is any insulin between U100 and U500. In other embodiments,the fluid may be, but is not limited to, opiates and/or otherpalliatives or analgesics, hormones, psychotropic therapeuticcompositions, or any other drug or chemical whose continuous dosing isdesirable or efficacious for use in treating patients. Single fluids andcombinations of two or more fluids (admixed or co-administered) may bedelivered using the fluid delivery device 110. As used herein “patients”or “user” can be human or non-human animals; the use of the fluiddelivery device 110 is not confined solely to human medicine, but can beequally applied to veterinarian medicine.

The fluid delivery device 110 may dispense the fluid over a sustainedperiod of time (i.e., basal delivery). In one embodiment, the fluiddelivery rate is continuously or near continuously delivered to the userover the sustained period of time. The fluid delivery device 110 mayalso be capable of dispensing a supplementary amount of fluid, inaddition to the basal amount, on demand, under patient control (i.e.,bolus delivery). In one embodiment, as discussed further below, thebolus amount delivered in a single, selectable administration ispre-determined. In preferred embodiments, the fluid delivery device 110is hydraulically actuated and comprises one or more reservoirs orchambers containing hydraulic fluid of a suitable viscosity fortransferring power from one or more actuators to the fluid andcontrolling the delivery rate as discussed further below.

One exemplary embodiment of the fluid delivery device 110 is shown inthe schematic of FIG. 3, illustrating select components and theirrelationships. The fluid delivery device 110 may have a first operablestate for dispensing or delivering the fluid through an infusion set orneedle 312 at a continuous or sustained basal dosage and a secondoperable state for delivering the fluid through the needle 312 at abolus dosage. In some embodiments, the fluid delivery device can be inboth the first and second operable states concurrently, i.e., deliveringa bolus dose in addition to a basal dose of fluid. In one embodiment,the bolus dosage is a fixed incremental dosage. In another embodiment,the bolus function is capable of delivering multiple discrete bolusincrements when activated by the user. In certain embodiments, the basalrate of delivery is predetermined and preset.

In one embodiment, the fluid delivery device 110 contains threehydraulic reservoirs or chambers, a hydraulic basal chamber 314, ahydraulic bolus chamber 316 and a hydraulic pump chamber 318. In someembodiments, the hydraulic bolus chamber 314 shares a common chamberwith the hydraulic pump chamber 318 and/or the flow between thehydraulic bolus chamber 316 and the hydraulic pump chamber 318 isunrestricted as described further herein. In a preferred embodiment, thehydraulic basal and bolus chambers 314, 316 are separately andindependently actuated by separate and independent basal and bolusactuators 320, 322.

Referring to FIG. 3, in one embodiment, the hydraulic basal and boluschambers 314, 316 act on the hydraulic pump chamber 318 which in turnacts on a fluid reservoir or delivery chamber 324, containing the fluid.In other embodiments, the hydraulic basal and bolus chambers 314, 316each act on a distinct pump chamber and each pump chamber isfunctionally connected to a separate fluid reservoir (not shown).

Referring to FIG. 2, the hydraulic basal, bolus and pump chambers 314,316, 318 may be defined by a manifold 226. In one embodiment, themanifold 226 is an integral one piece component 226. In one embodiment,the manifold 226 is comprised of a polymer. In one embodiment, themanifold 226 is comprised of polyvinyl chloride (PVC). In oneembodiment, the fluid reservoir 324 and a portion of the hydraulic pumpchamber 318 are defined by a fluid cartridge 228. In one embodiment, thefluid cartridge 228 is comprised of a polymer. In one embodiment, thefluid cartridge 228 is comprised of Topas 6017 S-04. The hydraulicbasal, bolus and pump chambers 314, 316, 318 and the fluid reservoir 324may be cylindrical. In other embodiments, the hydraulic pump chambers314, 316, 318 and the fluid reservoir 324 have any cross sectional shapesuch as square, rectangular or triangular. In one embodiment, a firstmoveable barrier 230 separates the basal actuator 320 and the hydraulicbasal chamber 314. In one embodiment, a second moveable barrier 232separates the bolus actuator 322 and the hydraulic bolus chamber 316. Inone embodiment, a third moveable barrier 234 separates the hydraulicpump chamber 318 and the fluid reservoir 324. The first, second andthird moveable barriers 230, 232, 234 may be pistons as describedfurther below. In other embodiments, the first, second and thirdmoveable barriers 230, 232, 234 are any barriers that can transfermovement between two chambers such as membranes or expandable walls.

The hydraulic basal and bolus chambers 314, 316 may be parallel, spacedon either side of and generally aligned with the hydraulic pump chamber318 and the fluid reservoir 324 as illustrated in order to provide amore compact configuration. In one embodiment, the hydraulic pumpchamber 318 is provided toward one side of the fluid delivery device110. In other embodiments, the hydraulic basal, bolus and pump chambers314, 316, 318 are arranged in any configuration that allows fluidcommunication and achieves the desired outer shape of the fluid deliverydevice 110 such as stacked in a triangle configuration.

The basal actuator 320 may act on the hydraulic basal chamber 314containing a hydraulic fluid to pressurize the hydraulic basal chamber314 and force a hydraulic fluid through a flow restrictor 336 into thehydraulic pump chamber 318. Generally, but not necessarily, thehydraulic fluid in hydraulic pump chamber 318 may be identical orsimilar in composition to the hydraulic fluid in hydraulic basal chamber314. Actuation of the basal actuator 320 may result in a flow ofhydraulic fluid from hydraulic basal reservoir 320 into the hydraulicpump chamber 318 at a reduced rate as compared to if the flow restrictor336 was not provided. As the volume of hydraulic fluid in the hydraulicpump chamber 318 increases, the third moveable barrier 234 is displaced,compressing or reducing the volume of the fluid reservoir 324 andcausing the fluid contained therein to be expelled through an outputorifice or needle 312 at a sustained basal rate. In one embodiment, thebasal rate is substantially constant.

In some embodiments, a bolus actuator 322 independently acts on thehydraulic bolus chamber 316. In one embodiment, the bolus actuator 322acts directly on the hydraulic pump chamber 318. It should beunderstood, however, that the invention is not limited to devicescomprising both a basal and a bolus capability. Devices of the inventionhaving one or more features described herein may comprise a basalcapability, a bolus capability, or both basal and bolus capabilities.

Both hydraulic bolus chamber 316 and hydraulic pump chamber 318 maycontain hydraulic fluid of an appropriate viscosity. Generally, but notnecessarily, the composition of the hydraulic fluid in hydraulic pumpchamber 318 will be identical or similar to the composition of thehydraulic fluid in hydraulic basal and bolus chambers 314, 316.Actuation or displacement of the bolus actuator 322 independentlydisplaces the third moveable barrier 234, compressing or reducing thevolume of fluid reservoir 324 and causing the fluid contained therein tobe expelled through an output orifice such as the needle 312. Concurrentoperation of both the basal and bolus actuators 320, 322 causescompression of fluid reservoir 324 by an amount greater than operationof either actuator alone.

When present, both the basal and bolus actuators 320, 322 may beintegrated within the hydraulically actuated system in a manner thatallows each function to provide independent displacement force onto acommon movable barrier 234, which in turn displaces fluid from within acommon fluid reservoir 324 to dispense the fluid from the device. Inother embodiments, the basal and bolus actuators 320, 322 may beintegrated within the hydraulically actuated system in a manner thatallows each function to provide independent displacement force ontoseparate moveable barriers (not shown), which in turn displace fluidfrom within separate fluid reservoirs (not shown). Examples of amulti-cartridge fluid delivery devices for use with the inventionspresented herein are disclosed in U.S. Patent Application PublicationNo. 2009/0240232 which is hereby incorporated by reference in itsentirety.

In one embodiment, the fluid delivery device 110 utilizes a combinationof force, high, very high or ultra high viscosity fluid, and flowrestriction to deliver the fluid on a continuous or sustained basis. Theflow restrictor 336 may facilitate continuous delivery of fluid at abasal rate by, among other aspects, creating a large pressuredifferential or pressure drop between the hydraulic basal chamber 314and the hydraulic pump chamber 318, allowing the system to tolerate awider range of frictional variations in the system such as movement ofthe third movable barrier 234 within the fluid cartridge 228, toleratesmall changes in the resistance to flow, and overcome potentialocclusions in the flow path. In one embodiment, the pressuredifferential between the hydraulic basal chamber 314 and the hydraulicpump chamber 318 during use is approximately 10:1. In one embodiment,the pressure differential between the hydraulic basal chamber 314 andthe hydraulic pump chamber 318 during use is approximately 46:1. In oneembodiment the hydraulic basal chamber 314 operates at a pressurebetween approximately 20 psi and between 70 psi. In one embodiment, thehydraulic basal chamber 314 operates at a pressure of approximately 46.8psi. In one embodiment, the hydraulic pump chamber 318 operates at apressure of approximately 0.5 psi to approximately 5 psi. In oneembodiment, the hydraulic pump chamber 318 operates at a pressure ofapproximately 1.2 psi.

The flow restrictor 336 is dimensionally adapted to control the rate offluid flow there through. In one embodiment, the flow restrictor 336 hasa diameter of approximately 1-1000 μm. It should be understood that allranges provided herein encompass both the beginning and end points ofthe range (e.g., includes 1 and 1000 μm in a range of from about 1 toabout 1000 μm), as well as all values in between. Whatever the shape ofthe flow restrictor 336, the cross sectional area and the length of theopening will be sized to achieve the flow rate desired. For example, theflow restrictor 336 may be about one-ten thousandths of an inch (or 2-3μm) in diameter. Depending on use, the flow restrictor 336 size may beanything, including but not limited to a diameter between 200 nm-500 nm,or 500 nm-1000 nm, or 1-2 μm, or 5-10 μm, or 10-1000 μm. In oneembodiment, the outer diameter of the flow restrictor 336 isapproximately 0.026 inches and the inner diameter of the flow restrictor336 is one of approximately 0.00758 inches, 0.00708 inches and 0.00638inches. In one embodiment, the length and outer diameter of the flowrestrictor 336 remains constant from device to device based on the sizeof the manifold 226 and the inner diameter of the flow restrictor 336may be altered to achieve the desired flow rate. Other sizes anddimensions of the flow restrictor 336 can be selected, and the size anddimension selected will depend upon the application at hand and, inparticular, the viscosity of the hydraulic fluid and the force appliedby the basal actuator 320. In one embodiment, the flow restrictor 336 iscomprised of topaz. Having a flow restrictor 336 comprised of topaz mayhelp to ensure that the flow restrictor 336 has a substantially accurateand constant cross sectional size and shape. Those of skill in the artwill understand that any suitable flow restrictor 336 may be employed,and that the size and the shape of the flow restrictor 336 can vary toachieve the desired flow rate of the fluid being mediated under theexpected conditions, including temperature and ambient pressure. Theflow restrictor 336 need not be circular in cross sectional shape, andcan be an oval, a square, a rectangle, a triangle, a polygon, orirregular in shape. The size and shape of the flow restrictor 336 may bedetermined empirically by testing the fluid flow of selected fluids atconditions of interest.

Referring to FIG. 4B, in one embodiment, the flow restrictor 336 extendsthrough a side 410 a of the fluid delivery device 110. In oneembodiment, the flow restrictor 336 extends through the hydraulic boluschamber 316 such that the hydraulic bolus chamber 316 is in fluidcommunication with the hydraulic basal chamber 314 through the flowrestrictor 336 and the hydraulic basal and bolus chambers 314, 316 areboth in fluid communication with the hydraulic pump chamber 318 througha nonrestrictive fluid passageway 438. In an alternative embodiment, thefluid passageway 438 is restrictive in order to retard the delivery rateof the bolus dose rather than having the delivery rate be nearly equalto the rate of movement of the bolus actuator 322.

With continued reference to FIG. 4B, in one embodiment, the flowrestrictor 336 includes a guide plug 440. In one embodiment, the guideplug 440 is sealed with the manifold 226 and positions the flowrestrictor 336 within the fluid passageway 438. In one embodiment, theguide plug 440 includes an opening 440 a for fluidly coupling the flowrestrictor 336 and the hydraulic bolus chamber 316. The flow restrictor336 may be secured to the manifold 226 by an epoxy. In one embodiment,the guide plug 440 and the flow restrictor 336 are comprised ofgenerally translucent materials such that the flow restrictor 336 may befixed to the manifold 226 by a UV curable resin after inserting the flowrestrictor 336 and the guide plug 440 within the manifold 226.

When the fluid delivery device 110 is activated, the basal actuator 320acts on the hydraulic fluid, increasing the pressure within thehydraulic basal chamber 314. As a result of this pressure increase, thehydraulic liquid within the hydraulic basal chamber 314 begins to flowthrough the flow restrictor 336 into the hydraulic bolus chamber 316. Inone embodiment, the bolus actuator 320 prevents expansion of thehydraulic bolus chamber 316 and the hydraulic fluid from the hydraulicbasal chamber 314 flows through the fluid passageway 438 and into thehydraulic pump chamber 318 where the hydraulic fluid displaces the thirdmoveable barrier 234 causing the fluid within the fluid reservoir 324 toexit the fluid delivery device 110 at a sustained basal rate. In oneembodiment, the basal rate is predetermined or preset by themanufacturer. Embodiments of the fluid delivery device 110 may be usedto continuously deliver a fluid over a range of time such as but limitedto 1 min, 1 hr, 6 hrs, 12 hrs, 1 day, 3 days, 5 days, 10 days, onemonth, etc. In certain embodiments, the fluid is expelled from the fluiddelivery device 110 at a basal rate selected from but not limited to:about 0.1 μl to about 10 μl per hour, about 10 to about 100 μl per hour,about 100 μl per hour to about 1 ml per hour, about 1 ml to about 100 mlper hour, or about 100 ml to about 200 ml per hour. In one embodiment,the basal rate is approximately 100 units/day which is 42 μl/hour or1000 μl/24 hours. The rate and delivery period selected will depend uponthe application at hand, and those of skill in the art will be able todetermine the proper dosage rate for a given application.

Referring to FIG. 3, embodiments of the fluid delivery device 110 may beconnected to an infusion set or needle 312 through a connection point atthe distal end 324 a of the fluid reservoir 324. In alternativeembodiments, the needle 312 may be located on the side wall of fluidreservoir 324. The needle 312 may be substituted with any deliverydevice such as a lumen, a needle set, a catheter-cannula set or amicroneedle or microneedle array attached by means of one or morelumens.

In one embodiment, basal flow rate is preset at the time of manufacturebased on the selection of the flow restrictor 336 in combination withthe viscosity of the hydraulic fluid and the force supplied on thehydraulic basal chamber 314. Alternatively, the length and/or diameterof the flow restrictor 336 can be adjusted on demand to alter the basalflow rate. In other embodiments, the flow restrictor 336 may beadjustable in size, as by means of an adjustable iris-type aperture ortelescoping restrictor passage miniature valve or paired gating slits(not shown). In an alternate embodiment, an electrical motor orpiezoelectric device (not shown) may be used to open or close theaperture, thus affecting the rate at which hydraulic fluid flows intopump chamber and displaces the third moveable barrier 234.

The hydraulic fluid may be any non-compressible, flowable material suchas gel or a collection of miniature solid beads. In one embodiment, thehydraulic fluid is an ultra pure, bio-inert material. In one embodimentthe hydraulic fluid is silicon oil. Useful viscosity of the hydraulicfluid is limited at its upper bound by the size of the flow restrictor336. At its lower bound, the hydraulic fluid must be viscous enough thatthe flow of the hydraulic fluid can remain highly regulated by thecombination of the pressure from the basal actuator 320 and the size ofthe flow restrictor 336 under a wide range of environmental conditions,especially in the presence of low atmospheric pressure and/or highambient temperature (where viscosity tends to decrease).

As used herein, “high viscosity” means the working hydraulic fluid has aviscosity grade of at least about ISO VG 20, or at least about ISO VG32, or at least about ISO VG 50, or at least about ISO VG 150, or atleast about ISO VG 450, or at least about ISO VG 1000, or at least aboutISO VG 1500 or more. In one embodiment the hydraulic fluid is very highviscosity fluid. As used herein, “very high viscosity” means the workinghydraulic fluid has a viscosity of from about 80,000 to about 180,000cPs. In one embodiment the hydraulic fluid is ultra high viscosity fluid(e.g., from about 180,000 to about 200 cPs). In one embodiment, thehydraulic fluid has a viscosity of 100,000 centiStokes.

In one embodiment, since viscosity varies inversely with temperature itis important to keep the hydraulic fluid at a generally constanttemperature. The fluid delivery device 110 is worn on the user's bodyfor the duration of administration of the fluid. The fluid deliverydevice 110 may be dimensionally adapted to attach to a user's body viaan adhesive patch 542 (see FIG. 5) as described further below.Accordingly, the fluid delivery device 110 will be exposed to a range ofenvironmental conditions commensurate with the patient's lifestyle.Without appropriate control of the variation in temperature of thehydraulic fluid, higher environmental temperatures may cause a reductionin viscosity, resulting in an increase in fluid flow and lowerenvironmental temperatures may cause an increase in viscosity, resultingin a decrease in fluid flow. In one embodiment, the hydraulic fluid isbrought to a generally constant temperature corresponding to thetemperature of the user's skin. Thus, in some embodiments, theconfiguration of the fluid delivery device 110 reduces the effect ofenvironmental temperature on the temperature of hydraulic fluid in thedevice. In one embodiment, because the temperature of the user's skin islikely higher than the storage temperature of the hydraulic fluid, theinitial fluid delivery rate is ramped up to the sustained basal deliveryrate.

Referring to FIG. 5, the fluid delivery device 110 may comprise aconductive thermal couple between the hydraulic fluid in the fluiddelivery device and the body of the wearer. The thermal couple utilizesthe consistent temperature of the body to regulate or moderate thetemperature of the hydraulic fluid which might otherwise be subject towide variation as a result of environmental temperature changes. Thismodulation reduces variation in the viscosity of the hydraulic fluid,thereby reducing undesired variation in the flow or delivery of thefluid caused by changes in ambient temperature.

In one embodiment, a thermally conductive path is provided between ahydraulic basal chamber 314 and the skin. The fluid delivery device mayhave an attachment surface 542 a having a first thermal conductanceconfigured to engage with a skin surface 544. In one embodiment, themanifold 226 housing the hydraulic basal chamber 314 has an outer wall226 a. In one embodiment, the outer wall 226 a has a portion 226 bproximate the attachment surface 542 a having a second thermalconductance; the second thermal conductance being greater than the firstthermal conductance of the attachment surface 542 a. The portion 226 bof the manifold proximate the attachment surface 542 a may be in directcontact with the skin surface 544 to allow for the hydraulic fluidwithin the hydraulic basal chamber to be kept at a substantiallyconstant temperature corresponding to the temperature of the skinsurface 544. In one embodiment, the attachment surface 542 a is integralwith an outer housing 546. In one embodiment, the attachment surface 542a is integral with a base 548 that is attached to the housing 546 (seeFIG. 2). As used herein, the base 548 may be considered to be part ofthe housing 546.

In another embodiment, thermal insulation is provided around theremaining surfaces of the hydraulic basal chamber 314 that are exposed,directly or indirectly such as through the housing 546 to the outsideenvironment. The thermal insulation may be any thermally conductivematerial and or an air space as shown. In a preferred embodiment, athermally conductive path is coupled with thermal insulation against theoutside environment (FIG. 5). In order to optimize the conductivecoupling between the skin surface 544 body and the hydraulic fluid, thehydraulic basal chamber 314 may be positioned in direct contact with thebody of the wearer. The fluid delivery device 110 may also be worn onthe belly of the user and covered with clothing to help further reducethe impact of changes in the ambient temperature.

As shown in FIG. 5, the portion 226 b of the manifold 226 housing thehydraulic basal chamber 314 may be proud of the surrounding surface ofthe base 548. In one embodiment, the portion 226 b of the manifold 226extending from the base 548 is generally tangent with attachment surface542 a of the adhesive patch 542 such the entire bottom surface 110 b ofthe fluid delivery device 110 is substantially planar. If present, theadhesive patch or pad 542 that affixes the fluid delivery device 110 tothe skin surface 544 is preferably relieved in this area, relief area542 a to further assure contact between the outer reservoir wall and theskin (see also FIG. 2). The adhesive patch 542 may partially extendbelow or over the manifold 226 to prevent the side of the manifold fromextending through relief area 542 a upon movement of adhesive patchextending outwardly from the fluid delivery device 110. In oneembodiment, the outer wall of the manifold 226 may be thinned (as shown)or the housing or other materials may be relieved in the area whichcontacts the skin surface 544 proximate the hydraulic basal chamber 314in order to reduce the mass of material separating the hydraulic fluidand the user to increase the thermal couple between the body and thehydraulic fluid.

In order to further reduce the influence of the outside environmentaltemperature on the temperature of the hydraulic fluid, one or moreadditional features may be incorporated into the device to insulate andisolate the hydraulic fluid from the outside environment. The hydraulicbasal chamber 314 can be a separate or isolated component from theremainder of the manifold (not shown). In one embodiment, the manifold226 and the housing 546 may be separated by an open air gap in the areasthat face toward the outside environment. To further isolate thehydraulic liquid, the air gap between the hydraulic basal chamber andthe housing 546 can be divided into separate air pockets to furtherdecouple or insulate the air within this gap. In one embodiment, thefluid reservoir 324 is thermally isolated from the skin surface 544. Inone embodiment, the air gap within the housing 546 substantiallysurrounds the fluid reservoir 324 to keep the fluid at a coolertemperature than the skin surface 544.

In one embodiment, one or more of the above configurations permits thefluid delivery device 110 to operate within a temperature range of 40°F. (5° C.) to 104° F. (40° C.). In the absence of a thermal coupling andif the hydraulic liquid were exposed to this full temperature rangeduring operation, the amount of resulting flow variation as a result ofthe change in the viscosity of the hydraulic liquid (typically on theorder of a 1% shift in viscosity per a 1° F. shift in temperature) couldintroduce too large a variation in the flow of the hydraulic fluidthrough the flow restrictor 336 yielding unacceptable drug deliveryperformance. In one embodiment, the improved temperature regulationfeatures of the fluid delivery device 110 result in less than a 1% shiftin viscosity per a 1° F. shift in ambient temperature. For example, thefeatures may result in a change of about 0.15%, 0.10% or 0.05% shift inviscosity per 1° F. shift in temperature. In one embodiment, only anapproximate 6° F. difference exists between the skin surface 544 and thehydraulic liquid at the low temperature limit and little to nodifference exists between the two measurements at the high temperaturelimit. As a result of this efficient couple between the skin surface 544and the hydraulic liquid, a change in temperature of less than 10° F.may be observed in the hydraulic liquid over a 65° F. change in ambient(environmental) temperature.

Referring to FIGS. 6A-6C, in one embodiment, the basal actuator 320exerts a force on the hydraulic basal chamber 314 to pressurize thehydraulic fluid. The basal actuator 320 may be any device that applies aforce on the hydraulic basal chamber 314 such as, but not limited to aperistaltic actuator, miniaturized bellows crank, or paired rollersbearing on hydraulic basal chamber 314, ratchet or stepper motor drivenunits that compress plates or other structures bearing on the hydraulicbasal chamber 314, electrically driven or piezoelectric mechanisms,expanding gas volume, thermal energy, or any other device or processcapable apply a pressure, either directly or indirectly, to the fluidbeing delivered. In one embodiment, the basal actuator 320 is open loopsuch that no electronics are required and the fluid delivery device 110may be purely mechanical.

In one embodiment, the basal actuator 320 is comprised of one or morebiasing members such as a first biasing member 650 and a second biasingmember 652. In one embodiment, the one first and second biasing members650, 652 are springs. In one embodiment, the first and second biasingmembers 650, 652 are helical compression springs. The force exerted by aspring in a compressed state at the start of travel is greater than theforce exerted by the spring in a less compressed state toward the end oftravel. The resulting force differential can impact the flow ofhydraulic fluid within the fluid delivery device 110 and thus impact theflow of the fluid being delivered.

In one embodiment, the difference in the force exerted by the first andsecond biasing members 650, 652 between the initial compressed state andthe less compressed state is reduced, thus reducing the amount ofpossible variation in the device's ability to achieve a sustained fluiddelivery rate. In one embodiment, the force differential between thecompressed and less compressed state is minimized by reducing the springrate (force/deflection) of the spring. The spring rate may be reduced byincreasing the length of the spring. In one embodiment, in order to keepthe fluid deliver device 110 as compact in size as possible and preventthe basal actuator 320 from having a decreased forced from beginning toend, multiple, coaxial stacked biasing members are used. In analternative embodiment, the second biasing member 652 is coupled to thefirst biasing member 650 in parallel. However, overlapping the first andsecond biasing members 650, 652 further reduces the size of the fluiddelivery device 110. In one embodiment, the cross sectional area of thehydraulic basal chamber 314 is larger than the cross sectional area ofthe fluid reservoir 324 to move the third moveable barrier 234 a greateraxial distance than the axial distance traveled by the first moveablebarrier 230 (see e.g. FIG. 4A). Reducing the spring force attenuationthat occurs over the total travel of the spring (stroke) duringoperation and maintaining a more constant spring force on the hydraulicfluid produces a more consistent flow of fluid from the device.

Referring to FIG. 6A, in one embodiment, the second biasing member 652is coupled to the first biasing member 650 in series and at leastpartially overlaps the first biasing member 650. In one embodiment, thefirst biasing member 650 is co-axial with the second biasing member 652.A co-axial arrangement of the first biasing member 650 and the secondbiasing member 652 may be preferred over a parallel arrangement. In oneembodiment, a proximal end 650 a of the first biasing member 650 iscoupled to the housing 546. In one embodiment, the proximal end 650 aabuts against a stop 654 extending from the base 548 (see also FIG. 2).In one embodiment, a sleeve 656 couples a distal end 650 b of the firstbiasing member with a proximal end 652 a of the second biasing member652, the sleeve 656 having a length generally equal to the length ofoverlap between the first and second biasing members 650, 652. In oneembodiment, the sleeve 656 has a body 656 a, a first flanged end 656 cand a second flanged end 656 b. The first flanged end 656 c may extendradially outwardly from the body 656 a of the sleeve 656 to engage thedistal end 650 b of the first biasing member 650. The second flanged end656 b of the sleeve 656 may extend radially inwardly from the body 656 aof the sleeve 656 to engage a proximal end 652 a of the second biasingmember 652. The body 656 a of the sleeve 656 may be generally hollow toallow the second biasing member 652 to extend through the sleeve 656 andengage the second flanged end 656 b. In one embodiment, the first andsecond biasing members 650, 652 have substantially equal spring ratessuch that the sleeve 656 “floats” between the first and second biasingmembers 650, 652 as they both expand. If one biasing member werestronger than the other, the stronger biasing member may dominate,preventing the other biasing member from expanding and negating thebenefit of the multi-biasing member configuration. In one embodiment,the difference in spring rate between the first and second biasingmembers 650, 652 is no greater than approximately 10%. In oneembodiment, the difference in spring rate between the first and secondbiasing members 650, 652 is no greater than approximately 3%.

The basal actuator 320 may include a plunger 658 extending through thefirst and second biasing members 650, 652. In one embodiment, the distalend 658 a of the plunger 658 has a radially outwardly extending flange658 b. The flange 658 b of the plunger 658 may engage the first moveablebarrier 230 and the distal end 652 b of the second biasing member 652. Aproximal end 658 c of the plunger 658 may be releaseably coupled withthe stop 654. The plunger 658 may extend through the stop 654 and bereleaseably coupled to the housing with a pin 660. In one embodiment,the pin 660 extends through the housing 546 and at least partiallythrough the plunger 658 and abuts against the stop 654 such that the pin660 prevents the plunger 658 from extending further into the hydraulicbasal chamber 314 due to the force of the first and second biasingmembers 650, 652 and can be removed from outside of the housing 546. Inone embodiment, the pin 660 is tapered to facilitate easier removal ofthe pin 660. The pin 660 may be coupled with a button cover 662 suchthat removal of the button cover 662 releases the plunger 658 in onestep by the user as described further below. FIGS. 6A-6C illustrate thebasal actuator 320 in the initial position (FIG. 6A), immediately afterremoving the pin 660 to activate or initiate the basal actuator 320(FIG. 6B) and the basal actuator 320 in use after a period of deliveringthe fluid (FIG. 6C).

Referring to FIG. 7, in one embodiment the configuration of the firstand second biasing members 650, 652 reduces the drop in force applied tothe hydraulic basal chamber 314 due to the expansion of the first andsecond biasing members 650, 652. For example, a single compressionspring S₁ compressed to a height of 0.75 inches will apply a force of5.7 pounds. When this single spring S₁ extends to a height of 0.935inches, the force applied drops to 5.34 pounds. This 6.3% drop in forcewould result in a proportional drop in hydraulic flow rate and in turnbasal delivery rate of fluid from the fluid delivery device 110. Toincrease the volume of the fluid displaced by the fluid delivery device110 without increasing the drop in force, the basal actuator 320 wouldneed to be lengthened proportional to the volume increase required. Inone exemplary embodiment, a dual overlapped spring configuration S₂compressed to a height of 0.945 inches will apply a force of 5.7 pounds.When the dual springs S₂ extend to a height of 1.283 inches, the forcedrops to 5.34 pounds. This 6.3% drop in force would be proportional tothe drop in flow rate; however, unlike the single spring S₁ thedisplacement volume is 83% greater while the length of the springassembly is only 25% greater. The dual spring assembly S₂ provides anadditional 83% increase in spring extension for a given loss of 0.36pounds in spring force. This provides additional basal capacity withoutincreasing losses due to spring extension. Conversely, the dual springS₂ could be used to deliver an equivalent volume (as compared with asingle spring embodiment S₁), with far less losses due to springextension over an equivalent extension length (approximately a 45%decrease in the force drop over an equivalent extension length). It isunderstood that a dual spring arrangement as shown is but oneembodiment, and that three or more springs may also be utilized.

In one embodiment, the basal actuator 320 has less than a 10% drop inforce applied to the hydraulic basal chamber 314 from beginning ofdelivery to end of delivery. In one embodiment, the basal actuator 320has less than an 8% drop in force applied to the hydraulic basal chamber314 from beginning of delivery to end of delivery. In one embodiment,the basal actuator 320 has less than a 6% drop in force applied to thehydraulic basal chamber 314 from beginning of delivery to end ofdelivery. In one embodiment, the basal actuator 320 has less than a 5%drop in force applied to the hydraulic basal chamber 314 from beginningof delivery to end of delivery. In one embodiment, the basal actuator320 has less than a 4% drop in force applied to the hydraulic basalchamber 314 from beginning of delivery to end of delivery. In oneembodiment, the basal actuator 320 has less than a 3% drop in forceapplied to the hydraulic basal chamber 314 from beginning of delivery toend of delivery.

In one embodiment, the basal actuator 320 has less than a predetermineddrop in force applied to the hydraulic basal chamber 314 from beginningof delivery to end of delivery as described above and has a length lessthan approximately 2 inches. In one embodiment, the basal actuator 320has less than a predetermined drop in force applied to the hydraulicbasal chamber 314 from beginning of delivery to end of delivery asdescribed above and has a length less than approximately 1.5 inches. Inone embodiment, the basal actuator 320 has less than a predetermineddrop in force applied to the hydraulic basal chamber 314 from beginningof delivery to end of delivery as described above and has a length lessthan approximately 1 inch. In one embodiment, the basal actuator 320 hasless than a predetermined drop in force applied to the hydraulic basalchamber 314 from beginning of delivery to end of delivery as describedabove and has a length less than approximately 0.8 inches.

Referring to FIG. 4A, in one embodiment, delivery consistency of thefluid is improved by reducing the amount of variation in force requiredto displace the third moveable barrier 234. In preferred embodiments,the force required to displace the third moveable barrier 234 is reducedor controlled by limiting or controlling one or more of the contactarea, contact force and coefficient of friction between the moveablebarriers 230, 232, 234 and their chamber walls and the compressibilityof the hydraulic fluid and the first moveable barrier 230.

Referring to FIG. 6A, the first moveable barrier 230 may have athickness t that is the minimum thickness to create a seal. In oneembodiment, the first moveable barrier has a thickness t ofapproximately 0.05 inches. In one embodiment, the first moveable barrier230 has a projection 230 a that extends into the distal end 658 a of theplunger 658. In one embodiment, the first moveable barrier 230 includesa rounded outer periphery 230 b for contacting the inside surface of themanifold 226. In one embodiment, the outer periphery 230 b of the firstmoveable barrier 230 is integral with the remainder of the firstmoveable barrier 230. In one embodiment, the first moveable barrier 230is comprised of Bromo-Butyl Rubber. In one embodiment, the firstmoveable barrier 230 has a durometer of 40 shore A.

Referring to FIGS. 8-9B, in one embodiment, the fluid delivery device110 is capable of dispensing fluid continuously or near continuously ata basal rate, as well as dispensing a supplementary amount of fluid orbolus on demand or under patient control. The fluid delivery device 110may allow for the user to deliver multiple discrete bolus amountswithout the user having to look at the fluid delivery device 110 or setthe bolus amount for delivery under and through the user's shirt (notshown). Each bolus dose may require two distinct motions to deliver thebolus dose. In one embodiment, a multiple button sequence to beperformed by the user to improve deliberate and correct bolus dosing. Ina preferred embodiment, the bolus delivery is operated by a cyclic(i.e., common, consistent, routine) mechanical system in which the userexecutes the same action one or multiple times to achieve one ormultiple bolus doses per cycle.

The number of bolus increments as well as the volume or dose per bolusincrement may be preset at the time of manufacture based on theselection of component parameters as described further below. The fluiddelivery device 110 can be preconfigured in a number of ways (fast/slowbasal rate, large/small bolus volume, many/few bolus increments) tofacilitate a variety of therapeutic needs.

Referring to FIGS. 9A and 9B, in one embodiment, each bolus delivery isindividually and deliberately activated by the user. For example, in oneembodiment each bolus delivery requires multiple (two or more)independent actions by the user, such as button actuations (via a bolusrelease button 964 and a bolus button 966), to insure that each bolusincrement (dose) is delivered by deliberate and intentional means andnot accidentally, incorrectly, or inadvertently delivered. The bolusbutton 966 and bolus release button 964 may be located on differentsides of the fluid delivery device 110. The user may slide his or herfinger along a first side of the fluid delivery device 110 until thebolus release button 964 is depressed and continue sliding their fingerup a second side of the fluid delivery device 110 until the bolus button966 is depressed. The user may slide their finger along the sides of thefluid delivery device 110 in order to find the bolus and bolus releasebuttons 964, 966 and the direction of movement of the user's finger ororientation of side of the fluid delivery device 110 and/or theconfiguration of the bolus and bolus release buttons 964, 966 help toindicate to the user which button is being depressed without having tolook at the fluid delivery device 110. In one embodiment, the bolusbutton 966 and the bolus release button 964 are on two different sidesof the fluid delivery device 110. In one embodiment, the different sidesof the fluid delivery device 110 have different length to facilitatetactile feedback when administering a bolus dose, allowing operationwithout direct line of sight (e.g., operating the fluid delivery device110 under one or more articles of clothing). In one embodiment, thebolus button 966 and the bolus release button 964 are located on thesame side of the fluid delivery device 110. In addition, an audible“click” feedback provided by depression of either button 964, 966 mayfurther facilitate predictable operation. In one embodiment, the bolusand bolus release buttons 964, 966 each have a distinct sound.

As illustrated in FIGS. 9A and 9B, the bolus release button 964 isdepressed (FIG. 9A) prior to depressing the bolus button 966 (FIG. 9B).In one embodiment, the bolus release button 964 enables the bolusactuator 322 for actuation by the bolus button 966 such that the bolusbutton 966 cannot be activated absent enablement by the bolus releasebutton 964. When the user is ready to deliver a bolus dose of fluid, heor she depresses the bolus release button 964. When depressed, the bolusrelease button 964 enables the bolus button 966 and after depressing thebolus button 966 causes the bolus actuator 322 to advance one bolusincrement.

In some embodiments, the fluid delivery device 110 delivers a discretedosage unit per actuation; the appropriate dosage unit will varydepending on the fluid to be delivered. In particular embodiments, forexample for delivery of insulin, the fluid delivery device 110 deliversfrom 1 to 4 units of insulin (e.g., 0.01 to 0.04 mL) per bolus increment(per “click”). In certain embodiments, the fluid delivery device 110 iscapable of delivering 36 bolus units (e.g., of insulin) in 2 unitincrements, i.e., 36 units delivered over the course of 18 “clicks.” Atthe same time, the fluid delivery device 110 may delivering anadditional amount (e.g., 20, 30, 40, etc. units) at the basal rate overthe entire delivery period. The total fluid capacity of the fluiddelivery device 110 is the sum of the basal and bolus capacities. Insome embodiments, the fluid delivery device 110 has a total fluidcapacity of 56, 66 or 76 units. In other embodiments, the fluid deliverydevice has a total fluid capacity of about 1200, 1500, or 2000 units.

Referring to FIG. 10A, the bolus actuator 322 may include a positionlock or rack 1068 that couples the bolus button 966 and the secondmoveable barrier 232. In one embodiment, the rack 1068 engages a housingpawl 1170 (see FIGS. 11A and 2) fixed relative to the manifold 226 thatprevents the rack 1068 and second moveable barrier 232 from movingoutwardly toward the bolus button 966. In one embodiment, the bolusbutton 966 is spring biased away from the second moveable barrier 232and includes a pawl 966 a that engages with the rack 1068 to advance therack 1068 one or more predetermined one way ratchets or teeth and resetsonce permitted.

Referring to FIG. 10B, the bolus release button 964 may engage with thebolus button 966 to control when the bolus button 966 is reset. In oneembodiment, the bolus release button 964 includes a projection 964 athat engages the bolus button 966 by selectively sliding through andbeing positioned within aperture 966 b of the bolus button 966 (shownbest in FIG. 2). In one embodiment, when the projection 964 a of thebolus release button 964 is within the aperture 966 b (as shown in FIGS.10B, 12B and 13B) bolus button 966 on either end of the aperture 966 babuts against the projection 964 a and prevents movement of the bolusbutton 966 in either direction. In one embodiment, depressing the bolusbutton 966 moves the projection 964 a out of the aperture 966 b andallows the bolus button 966 to be reset by the spring bias (as shown inFIG. 11B). In one embodiment, the bolus release button 966 is springbiased such that releasing the bolus release button 966 after depressingthe bolus release button 966 biases the projection 964 a against theside of the bolus release button 964 adjacent to the aperture 966 b andsuch that once the aperture aligns with the projection 964 a upondepressing the bolus button 966 the projection 964 a immediately mateswith the aperture 966 b. In one embodiment, the bolus button 966 isspring biased with a torsion spring 1072. In one embodiment, the sametorsion spring 1072 that biases the bolus button 966 spring biases thebolus release button 964.

FIGS. 10A-13B depict an exemplary sequence of events in bolus dosing.FIGS. 10A and 10B depict the position of the bolus button 966 and bolusrelease button 964 prior to bolus dosing; the bolus release button 964is in the enabled position, and the bolus button 966 is locked in thedepressed position. FIGS. 11A-11B depict the enabling step; the userdepresses the bolus release button 964 to its stop position, causing thebolus button 966 to move to the extended position. The bolus button 966is now enabled for one incremental dose. FIGS. 12A-12B illustratedelivery of a bolus dose; the user depresses the bolus button 966 to thestop position, causing the bolus actuator 322 to advance one increment,displacing the second moveable barrier 232 and dispensing one bolusdose. The bolus release button 964 is returned to the enabled position.FIGS. 13A-13B illustrate delivery of the last bolus dose of the device;the user depresses the bolus button 966 to its stop position, causingthe bolus actuator 322 to advance one increment, displacing the secondmoveable barrier 232 and dispensing the final bolus dose. This activatesa lock-out feature of the fluid delivery device 110, causing the bolusrelease button 964 to slide through an aperture 1068 a (see FIG. 8) inthe rack 1068 to the lock-out position. In one embodiment, once thebolus release button 964 extends outwardly through aperture 1068 a, thetorsion spring 1072 slides off a ledge 546 b of the housing 546 andextends between the bolus release button 964 and the ledge 546 b toretain the bolus release button 964 in the lock-out position (See FIG.13B). The bolus release button 964 may be locked in place to preventsubsequent operation and to indicate to the user that all of the bolusdoses have been delivered.

In one embodiment, the bolus button 966 remains in the depressedposition slightly proud of (i.e. raised, projecting or extending from)the outer device surface of the housing 546. As a result of the user'spressing the bolus release button 964, the bolus actuator 322 may engageone bolus increment as the bolus button 966 extends further from thehousing 546. When the user then depresses the bolus button 966 back toits original position (i.e., slightly proud of the housing 546), thebolus actuator 322 advances the second moveable barrier 232 a fixedamount or increment. The resulting movement of the second moveablebarrier 232 displaces the hydraulic fluid and in turn displaces thethird movable barrier 234 by essentially the same volume increment,dispensing a bolus dose of fluid from the fluid delivery device 110.

The second moveable barrier 232 may be capable of maintaining a seal asit translates within the hydraulic bolus chamber 316. In one embodiment,the second moveable barrier 232 is displaced by the rack 1068 by thedistance equal to one ratchet spacing at a time per activation of thebolus button 966.

Referring to FIG. 14, in one embodiment, the fluid reservoir 324initially is filled with a quantity of the fluid to be delivered to theuser. In another embodiment, the fluid reservoir 324 may be filled bythe user prior to use. In one embodiment, the fluid cartridge 228 of thefluid reservoir 324 is comprised of a rigid material. In one embodiment,the fluid cartridge 228 is comprised of Topas 6017 S-04. In someembodiments, the fluid cartridge 228 may be comprised of a polymer dueto the reduce length of time of exposure of the fluid to the fluidcartridge 228 (for example, 24 hours after the user fills the fluidcartridge 228 and uses it) where previous fluid cartridges had to becomprised of a glass or other material having lower leachable andextractible properties for storage of the fluid over an extended periodof time. Additionally, because known delivery devices includeelectronics, such devices are not practical for one day disposable useas is a purely mechanical device as disclosed in certain embodiments ofthe fluid delivery device 110 herein.

In the case of a medicament, the quantity of fluid may be pre-determinedby a medical professional in order to provide the necessary dosing overa pre-determined period of time. The volume of the fluid reservoir 324may be about 100 μl, 500 μl, 1 ml, 3 ml, 5 ml, 10 ml, 30 ml, 50 ml, 100ml or more. The fluid cartridge 228 may include a septum 1474 within thedistal end of the fluid cartridge 228. In one embodiment, the septum1474 acts as a stopper. In other embodiments, the septum 1474 may be atleast portion of the sidewall (not shown). In one embodiment, the fluidcartridge 228 includes a spacer 1476 on the hydraulic fluid side of thethird moveable barrier 234 such that the size of the fluid cartridge 228may adapt to a range of fluid volumes by varying the size of the spacer1476. In one embodiment, the space 1476 may be brightly colored to helpindicate the level of fluid within the fluid cartridge 228. The fluidcartridge 228 may include a seal 1478 that has an opening 1478 a (seeFIG. 2) such that the seal 1478 seals the fluid cartridge 228 to themanifold 226 while allowing the hydraulic fluid to pass through toeither the spacer 1476 and/or the third moveable barrier 234.

In one embodiment, the septum 1474 is composed of a flexible materialsuch as rubber and fits within fluid cartridge 228, forming a seal onthe end opposite the third moveable barrier 234. The septum 1474 may bea hollow cylinder open only at the end that is installed in the fluidcartridge 228. The septum may remain stationary and is positioned toalign with the needle 312. When the needle 312 pierces the side theseptum 1474, the fluid path between the fluid delivery device 110 andthe outside environment is opened, allowing the fluid to flow from thefluid delivery device 110. In one embodiment, the septum 1474 is exposedthrough a side of the housing 546 to allow for the user to fill thefluid reservoir 324. The septum 1474 may have a hardness sufficient toallow the needle 312 to move relative to the remainder of the fluiddelivery device 110 as described in further detail below. In oneembodiment, the septum 1474 has a hardness of 50 shore A.

Referring to FIG. 15, the third moveable barrier 234 may be a plungerthat slides within the fluid cartridge 228. Typically, pistons may haveimprecise sizing and compressibility characteristics because the impacton the delivery rate is not critical. In one embodiment, the thirdmoveable barrier 234 of the fluid delivery device 110 however, isconfigured to minimize any impact on the fluid delivery rate. In oneembodiment, the third moveable barrier 234 is comprised of a flexiblematerial to form a seal between the hydraulic fluid and the fluid to bedelivered to the user. In one embodiment, the third moveable barrier 234has a similar configuration to the second moveable barrier 232. In oneembodiment, the axial compressibility is minimized. In one embodiment,the axial compressibility of the second and third moveable barriers 232,234 may be greater than the axial compressibility of the first moveablebarrier 230 due to the lower pressure differentials acting on the secondand third moveable barriers 232, 234. In such an embodiment, the loweraxial compressibility allows for a thickness or length L that is greaterthan the thickness t of the first moveable barrier 230 and allows twopoints of contact. In one embodiment, the third moveable barrier 234 iscomprised of a single material having a durometer between approximately35 and approximately 65 shore A. In one embodiment, the durometer of thethird moveable barrier 234 is between approximately 35 and approximately65 shore A for a fluid cartridge 228 comprised of a polymer. In anotherembodiment, the durometer of the third moveable barrier 234 is betweenapproximately 35 and approximately 45 shore A for a fluid cartridge 228comprised of glass. In one embodiment, the durometer of the thirdmoveable barrier 234 is 55 shore A with a fluid cartridge 228 comprisedof a polymer. In one embodiment, the third moveable barrier 234 iscomprised of Butyl Rubber. In one embodiment, the third moveable barrier234 is coated with 0.0001 inch parylene C. In one embodiment, the thirdmoveable barrier 234 has a minor diameter of approximately 0.2425 inchesand a major diameter of approximately 0.2615 inches±0.002 inches.

In one embodiment, the third moveable barrier 234 includes a body 234 ahaving a first end 234 b and a second end 234 c. The third moveablebarrier 234 may include a first flange 234 d and a second flange 234 e.In one embodiment, the first and second flanges 234 d, 234 e areintegral with the body 234 a and extend radially outwardly from the body234 a proximate the first end and second ends 234 b, 234 c respectively,in an uncompressed state. The first and second flanges 234 d, 234 e maybe configured such that contact with the fluid cartridge 228 isminimized. Having the first and second flanges 234 d, 234 e be integralwith the body 234 a may prevent roll over and flash points that occurwith the use of separate o-rings. In one embodiment, the first andsecond flanges 234 d, 234 e have a curved cross sectional periphery inthe uncompressed state. In one embodiment, the curve has a substantiallyconstant radius r in the uncompressed state. In one embodiment, thefirst and second flanges 234 d, 234 e are spaced from the first andsecond ends 234 b, 234 c respectively in order to provide proper supportfor the first and second flanges 234 d, 234 e.

In one embodiment, control of the contact area of third moveable barrier234 to the inner wall of the fluid cartridge 228 is addressed by thestructural design of the first and second flanges 234 d, 234 e. In oneembodiment, the first and second flanges 234 d, 234 e have a circularside cross sectional profile. In this embodiment a circular profile onthe outer surface of a plunger constructed of an elastomeric materialpresents a small contact area that can be deformed with a minimal changein force. Though individual pistons and cylinders vary in size due tomanufacturing tolerances, the contact area variation is reduced by theconfigurations disclosed herein. Providing two flanges providesredundant sealing to insure the isolation of the fluid from thehydraulic fluid.

In additional embodiments, the coefficient of friction between the thirdmoveable barrier 234 and the fluid reservoir 324 is controlled byappropriate selection of contact materials. In this embodiment, one ormore suitable coating agents are applied to the outer surface of thethird moveable barrier 234 and/or the inner surface of the fluidreservoir 324 to minimize both the coefficient of friction and thevariation of the coefficient of friction from device to device. Inaddition, a coating process using Parylene ‘C’ material may be used. Afilm coating with Parylene ‘C’ material greater than about 0.0001 inch(2.5 microns) has proven to contribute to controlling the movement ofthe third moveable barrier 234. The Parylene coating is preferablyconformal and of uniform thickness and is substantially free of anyvoids or pinholes. Parylene may be applied at the molecular level by avacuum deposition process at ambient temperature. Film coatings fromabout 0.100 to 76 microns are possible in a single operation. In oneembodiment, no catalysts or solvents are required, and no foreignsubstances are introduced that could degrade the coated surface.Parylene ‘C’ is a modified version of Parylene which may provide abetter combination of electrical and physical properties including lowmoisture and gas permeability.

Referring to FIGS. 16A-16C, in one embodiment, the fluid delivery device110 has multiple operable states. In a first operable state or storageposition (FIG. 16A), the needle 312 is not engaged or is separated fromthe fluid reservoir 324 and does not extend from the housing 546 (i.e.not inserted into the body). In a second operable state or engageableposition (FIG. 16B), the needle 312 is able to be engaged with the fluidreservoir 324. In a third operable state or engaged or activatedposition (FIG. 16C), the needle 312 is in fluid communication with thefluid to be delivered and is inserted into the body or available forinsertion into the body. In a fourth operable state or disengaged ordisposable position (not shown), the needle 312 is again separated fromthe fluid to be delivered, is not inserted into the body, and is fixedlyretained (locked) within the housing 546.

In one embodiment, the button cover 662 shrouds the needle 312preventing accidental depression of the needle 312 during handling andshipping of the fluid delivery device 110. In one embodiment, the buttoncover 662 includes a flange 662 a to facilitate grasping and removingthe button cover 662 by the user. In one embodiment, the button cover662 has a projection 662 b for coupling with the pin 660. The buttoncover 662 may include indicia 662 c such as the word “Remove” toindicate what the user should do with the button cover 662 (See FIG. 2).In one embodiment, the button cover 662 includes a tab 662 d forproviding leverage against the housing 546 as the button cover 662 isremoved by holding the flange 662 a on the opposite side of the buttoncover 662. In one embodiment, when the button cover 662 is removed, aneedle button 1680 coupled to the needle 312 is exposed (FIG. 16B).

In one embodiment, the needle 312 is fixed to the needle button 1680. Inone embodiment, the needle 312 is heat staked to the needle button 1680at points 1680 a as shown in FIG. 19. In other embodiments, the needle312 is moveable relative to the needle button 1680. In one embodiment,removal of the button cover 662 simultaneously removes the pin 660 fromthe basal actuator 320 to release or activate the basal actuator 320such that it acts on the hydraulic fluid. Thus, in preferredembodiments, the button cover 662 performs the dual functions ofshrouding and protecting the needle button 1680 to prevent unintentionalactivation of the needle 312 and simultaneously controls activation ofthe basal actuator 320.

Referring to FIGS. 17 and 18, in one embodiment, the needle button 1680deploys the needle 312 when depressed (FIG. 18). The needle button 1680may be spring biased away from the septum 1474. In one embodiment, theneedle button 1680 is spring biased by a compression spring 1784 asdescribed further below. A first force may be required to move theneedle button 1680 from the initial position. In one embodiment, thefirst force is greater than a second force that is required to move theneedle button 1680 the remainder of way (i.e. at least greater than theforce from the spring 1784) to the engaged position to help usersovercome the fear of depressing the needle 312 into the skin surface544. In one embodiment, one or more breakable tabs 1682 extend from thehousing 546 such that the tabs 1682 break upon providing the first forcein the first direction d such that the user completes the deployment orinsertion of the needle 312 quickly and fully after the tabs 1682release the needle button 1680 and helps to prevent failed or partialinsertion or engagement attempts. In the deployable position, the needle312 may be moveable nearly exclusively in the engagement direction (i.e.toward the septum 1474) such that the needle 312 enters the septum andthe user with little to no movement in the transverse direction to helpensure proper engagement. Once the needle 312 is in the engagedposition, the needle 312 may then move relative to the remainder of thefluid delivery device 110 to reduce pain caused by movement of theneedle 312 relative to the user as described below. In one embodiment,the needle 312 is flexible and restraining movement of the needle 312during engagement aids in proper engagement of the needle 312.

In one embodiment, the needle 312 extends from the fluid reservoir 324,through the pierceable member or septum 1474 at a connection point 1474a and out of the housing 546. The needle 312 may be moveable relative tothe septum 1474 or the fluid delivery device 110 may move relative tothe needle 312 such that when the needle 312 extends into the skinsurface 544 in the engaged position, movement of the needle 312 relativeto the user caused by movement of the fluid delivery device 110 isreduced. Minimizing the movement of the needle 312 relative to the usermay help to reduce pain or “pinching” caused by the needle 312.

In one embodiment, the needle 312 is configured to translate in adirection perpendicular to the septum 1474, e.g. direction d in FIG. 18,and pivot about the connection point 1474 a in all directions. In oneembodiment, the pivot of the needle 312 about the connection point 1474a is within the boundaries of an imaginary hour glass shaped path (notshown) proximate the septum 1474. In one embodiment, the entire needle312 is configured to pivot about the connection point 1474 a due to theflexibility of the septum 1474 and is limited by the connection betweenthe needle button 1680 and the housing 546. In one embodiment, theneedle 312 is configured to be entirely within or at least shrouded bythe housing 546 and disengaged from the fluid reservoir 324 in aninitial position (FIG. 17) and fluidly coupled with the fluid reservoir324 and extending from the housing 546 in an engaged position (FIG. 18).In one embodiment, the needle 312 is configured to pierce the pierceablemember 1474 after extending from the housing 546 when moving the needle312 from the initial position to the engaged position such that thefluid does not exit onto the skin surface 544 and interfere with theadhesion of the adhesive patch 542. In one embodiment, the needle 312 isconfigured such that the needle 312 pierces the skin surface 544approximately simultaneously to when the needle 312 pierces thepierceable member 1474.

In one embodiment, the needle 312 is generally J-shaped such that itstwo ends are pointing in the same direction but are axially andlaterally spaced from one another. In one embodiment, the needle 312includes two generally perpendicular bends with one end of the needle312 being shorter than the other. In one embodiment, the septum 1474, orat least a surface tangent to the connection point 1474 a, is generallyparallel to a bottom surface 110 b of the housing from which the needle312 extends in the engaged position. In one embodiment, the needle 312is a microneedle. In one embodiment, the needle 312 is a fine gaugeneedle. In one embodiment, the needle 312 is a 30 gauge needle. In oneembodiment, both ends of the needle 312 are beveled to help facilitatepiercing of the septum 1474 and the skin surface 544. In one embodiment,the needle 312 is configured to rotate about an imaginary axis A thatextends through the connection point 1474 a perpendicular to the septum1474 as shown in FIG. 18 such that the fluid delivery device may rotateabout the axis A without, or at least reduces, the end of the needle 312extending into the user moving in an arched path.

In one embodiment, once the needle 312 is in the engaged position theneedle button 1680 is locked into place and the fluid in the fluidreservoir is in liquid communication with the outside environment (e.g.,the body) via the needle 312. The locking member 2088 may be configuredto keep the first and second ends of the needle 312 disengaged from theuser and the fluid reservoir 324 and contained within the housing 546 ina locked position upon moving the needle from the engaged position (FIG.18) to the locked position (FIG. 23). In the locked position, the needle312 may be kept from redeployment or engagement such that the housing546 acts as its own sharps container. In one embodiment, the needle 312is moved to the locked position through use of a needle release or lockbutton 1886.

Referring to FIG. 20, in certain embodiments, the spring 1784 is locatedbetween the needle button 1680 and the base 548 and surrounds a boss orsleeve 1680 a of the needle button 1680 extending partially over theneedle 312. In one embodiment, the spring 1784 becomes compressed whenneedle button 1680 is locked in the depressed, engaged or insertedposition (FIG. 18) to bias the needle button 1680 away from the septum1474. The needle button 1680 may be retained in the inserted position bya locking member as described further below. The locking member 2088 maybe released when the user is finished with the fluid delivery device110. In one embodiment, prior to removing the fluid delivery device 110from the body, the user activates the lock button 1886 to retract theneedle 312 from the user and into the housing 546. In other embodiments,the needle 312 is automatically retracted after the fluid reservoir 324is substantially empty or automatically upon removal of the fluiddelivery device 110 from the skin surface 544.

In one embodiment, the locking member 2088 is a spring. In oneembodiment, the locking member 2088 is comprised of a helical torsionspring. In one embodiment, the locking member 2088 biases the lockbutton 1886 and interacts with features of the needle button 1680 andthe base 548 to releaseably retain the needle 312 in the depressed orinserted position (FIG. 18) and unrealeaseably locked in the lock-outposition (FIG. 22).

In one embodiment, the locking member 2088 is coupled to or engageablewith the lock button 1886. In one embodiment, the lock button 1886 has asurface 1886 a exposed through the housing 546. In one embodiment, thesurface 1886 a of the lock button 1886 is exposed through an aperture inthe housing 546 on a first side of the housing 546 and the housing 546has a surface on a second side of the housing 546 opposed to the firstside of the housing and generally aligned with the lock button 1886 suchthat the user can grip the lock button 1886 and the housing 546 betweena thumb and a finger to activate the lock button 1886 within engagingthe bolus release button 964 preventing accidental activation of thelock button 1886 when using the bolus actuator 322. The lock button 1886may include at last one projection 1886 b extending from the surface tohelp facilitate grip with the user's hand. In one embodiment, the atleast one projection 1886 b is ramped (see FIG. 23A) to furtherfacilitate grip and help indicate to the user by feel which directionthe lock button 1886 should be urged.

Referring to FIG. 20, in one embodiment, the sleeve 1680 a surrounds theneedle 312 and the locking member 2088 is spring biased toward thesleeve 1680 a. In one embodiment, the sleeve 1680 a has at least oneabutment surface configured to engage with the locking member 2088 toprevent at least one of engaging and disengaging the needle 312. In oneembodiment, the at least one abutment surface includes a first abutmentsurface 1680 b and a second abutment surface 1680 b.

In one embodiment, the first abutment surface 1680 b is axially spacedalong the needle 312 from the second abutment surface 1680 c. In oneembodiment, the first abutment surface 1680 b is a radially inwardlyextending groove. In one embodiment, the second abutment surface 1680 cis the distal end of the sleeve 1680. In other embodiments, the firstand second abutment surfaces 1680 b, 1680 c are any surface such as aprojection or groove that axially engages with the locking member 2088.In one embodiment, the base 548 includes an upwardly extending boss orguide 2090 for receiving and guiding the sleeve 1680 a and engaging withthe locking member 2088. In one embodiment, the guide 2090 loosely fitsover the sleeve 1680 a to allow some non-axial movement or pivot of theneedle button 1680 relative to the base 2090 for the pivoting of theneedle 312 as described above. The guide 2090 may include a groove 2090a configured to receive the locking member 2088. In one embodiment, thegroove 2090 a aligns with the first abutment surface 1680 a in theengaged position (FIG. 18) and aligns with the second abutment surface1680 b in the locked-out position (FIG. 22). In one embodiment, thelocking member 2088 engages with the first abutment surface 1680 b toreleaseably retain the needle 312 in the engaged position (FIG. 18) andlocking member 2088 engages with the second abutment surface 1680 c tounreleaseably retain the needle 312 in the locked position (FIG. 22). Inone embodiment, the lock button 1886 is configured to position thelocking member 2088 into the locked position upon disengaging the needle312 from the user.

Referring to FIG. 20, in one embodiment, the locking member 2088 isconfigured to provide an audible feedback upon retaining the needle 312in the engaged position so the user is assured that the needle 312 hasbeen fully deployed and in the engaged position. In one embodiment, theguide 2090 includes a projection 2090 b that facilitates creating anaudible “click” by sliding the locking member 2088 over and into thegroove 2090 a and first abutment surface 1680 a. In one embodiment, theprojection 2090 b is a ramped surface 1886 c that is selectablyengageable with the locking member 2088. In one embodiment, the lockingmember 2088 is biased against the guide 2090 above the groove 2090 a(see FIG. 21) and depressing the needle button 1680 engages a surface1680 d with the locking member 2088 and slides the locking member 2088down the guide 2090 over the projection 2090 b and into the alignedgroove 2090 a and first abutment surface 1680 a. In one embodiment, theneedle button 1680 includes a cutout 1680 e to fit over the septum 1474.In one embodiment, the cutout 1680 e is loosely sized to the contour ofthe septum 1474 to support the needle 312 relative to the housing 546but allows for the movement of the needle 312 described above.

In one embodiment, when the user depresses the needle button 1680, afree end or first arm 2088 a of the locking member 2088 is moved fromits initial preloaded position against the guide 2090 and into thealigned groove 2090 a and first abutment surface 1680 a. When the lockbutton 1886 is depressed the ramped surface 1886 c may force the firstarm 2088 a of the locking member 2088 from the first abutment surface1680 a momentarily, allowing needle button 1680 to retract to theupright or initial position as a result of the force from the spring1784. As the user continues to press the lock button 1886, the end ofthe first arm 2088 a may abut a surface within the housing 546,preventing further rotation (similar to the position shown in FIG. 21).The mid section of the first arm may then deflect over the rampedsurface 1886 c of the lock button 1886 allowing the first arm 2088 a tospring back into the groove 2090 a (FIG. 22). The second abutmentsurface 1680 c of the needle button 1680 may then be axially above thefirst arm 2088 a extending across the guide 2090 preventing the needlebutton 1680 and needle 312 from further translation orre-depression/re-deployment (FIG. 22).

Referring to FIGS. 23A-23C, in one embodiment, the lock button 1886 isconfigured to release the locking member 2088 only after completing twodistinct motions to prevent accidental release of the locking member2088. In one embodiment, the lock button 1886 is configured to move in afirst direction l₁ and move in a second direction l₂ only after moving apredetermined distance in the first direction. In one embodiment, thelock button 1886 includes at least one projection 1886 d and the housingor base 548 includes at least one slot 548 a each configured to receiveone of the at least one projection 1886 d. In one embodiment, each atleast one slot 548 a is unaligned with one of the at least oneprojection 1886 d in an initial position (FIG. 23A) and aligned with oneof the at least one projection 1886 d after moving the lock button 1886the predetermined distance in the first direction l₁ (FIG. 23B) and eachat least one slot 548 a receiving one of the at least one projection1886 d after moving the lock button 1886 a predetermined distance in thesecond direction l₂. In one embodiment, the first and second directionsl₁ and l₂ are linear translations. In one embodiment, the firstdirection is perpendicular to the second direction as shown in FIGS.23A-23C. In other embodiments, the first and second directions are anydirections such as curved and/or rotational. In one embodiment, the lockbutton 1886 is spring biased in a direction opposite the firstdirection. In one embodiment, the lock button 1886 is retained in thefirst direction by one or more breakaway tabs (not shown). In otherembodiments, the lock button 1886 is comprised of more than one button.

Referring to FIG. 2, in some embodiments, the fluid delivery device 110may include one or more view windows. View windows can be, for example,on the top side and/or the bottom side of the fluid delivery device 110.These view windows allow light penetration to facilitate point of carefilling of the fluid reservoir 324, to increase viewability to determinelevel and viability of fluid, and to enhance user confidence by allowingobservation by allowing the user to observe the relative position of thethird moveable barrier 234 during delivery and/or filling. In oneembodiment, the housing 546 includes a window 546 a generally alignedwith the fluid cartridge 228. In one embodiment, the adhesive patch 542includes a window 542 b. The window 542 b may be a translucent area orsimply a gap in the material. In one embodiment, the windows 542 a and542 b are generally aligned. In one embodiment, the remainder of theexposed housing 546 is opaque such that only the fluid cartridge 228 isvisible through the housing 546.

In some embodiments, the fluid delivery device 110 includes an adhesiveto facilitate attachment of the fluid delivery device 110 to the skinsurface 544 of the user (see e.g. FIG. 9A). The adhesive strength shouldpreferably be sufficient to adhere the fluid delivery device 110 to theskin surface 544 of the user for the duration of treatment with thedrug-filled fluid delivery device 110. Thus, adhesive strength may varydepending on the duration of treatment (e.g., 72 hours, 48 hours, 24hours, 18 hours, 12 hours, etc.). Moreover, the adhesive should be suchthat the fluid delivery device 110 is easily removable without unduediscomfort or pain or difficulty upon completion of use. In someembodiments, the adhesive may be relieved in certain areas, e.g., in thearea of the hydraulic basal chamber 314 (see e.g. area 542 a in FIG. 2),the fluid reservoir 324 (see e.g. area 542 b in FIG. 2) and/or proximatethe needle 312 (see e.g. area 542 c in FIG. 2), to facilitate contact ofthe fluid delivery device 110 with the skin surface 544 of the user.

The adhesive may be combined with a pad to form an adhesive patch 542.In one embodiment, the adhesive patch 542 is a non-woven foam pad. Inone embodiment, the adhesive patch 542 is comprised of a medical foamadhesive manufactured by 3M®. In one embodiment, the adhesive patch 542is comprised of 3M® 9776 material. In one embodiment, the outerdimension of the adhesive patch 542 extends beyond the outer dimensionsof the housing 546 to allow greater adhesive surface area and/or greaterflexibility of the adhesive patch 546 to contour to the user's bodyshape. In certain embodiments, extended area is, for example, about0.010 inches, 0.100 inches, 0.250 inches, 0.500 inches or more from thehousing 546. The adhesive patch 542 may be capable of movement (e.g.flexing, stretching) in multiple orientations to improve comfort of wearand reduce pinching or tightness or the wearer's perception of pinchingor tightness. In one embodiment, the adhesive is initially covered by aremovable film 292 (see FIG. 2). In one embodiment, the film 292includes a tab 292 a extending outwardly from the adhesive patch 542 tofacilitate removal from the adhesive patch 542 just prior to applyingthe fluid delivery device 110 to the skin surface 544.

Referring to FIGS. 16A-16B, in exemplary use, the user removes the fluiddelivery device 110 from a storage package (not shown). The user maythen fill the fluid cartridge 228 with the fluid. In one embodiment, thefluid cartridge 228 is pre-filled. Once the fluid cartridge 228 isfilled, the user may remove the button cover 662 exposing the needlebutton 1680 and simultaneously activating the basal actuator 320.Referring to FIG. 9A, the user may then remove the film 292 from theadhesive patch 542 and place the fluid delivery device 110 on the skinsurface 544. In other embodiments, the fluid delivery device 110 isplaced on the skin surface 544 before removing the button cover 662.Once the fluid delivery device 110 is on the skin surface 544 and thebutton cover 662 is removed, the user may then depress the needle button1680 to engage the needle 312 (sec FIG. 18) and fluidly couple the userand the fluid reservoir 324. Once the needle 312 is engaged and whenappropriate, the user may then activate the bolus release button 964(FIG. 9A) and then activate the bolus button 966 (FIG. 9B) to deliver abolus dosage. Once the delivery period (e.g. 24 hours) is complete orthe user otherwise wants to remove the fluid delivery device 110, theuser depresses the lock button 1886 (see FIGS. 23A-23C) to retract theneedle 312 into the housing 546 (FIG. 22). Once the needle 312 isshrouded by the housing 546, the user may then remove the fluid deliverydevice 110 from the skin surface 544, dispose the fluid delivery device110 and repeat the above steps to install a fresh fluid delivery device110.

It will be appreciated by those skilled in the art that changes could bemade to the exemplary embodiments shown and described above withoutdeparting from the broad inventive concept thereof. It is understood,therefore, that this invention is not limited to the exemplaryembodiments shown and described, but it is intended to covermodifications within the spirit and scope of the present invention asdefined by the claims. For example, specific features of the exemplaryembodiments may or may not be part of the claimed invention and featuresof the disclosed embodiments may be combined. The words “inwardly” and“outwardly” refer to directions toward and away from, respectively, thegeometric center of the fluid delivery device. Unless specifically setforth herein, the terms “a”, “an” and “the” are not limited to oneelement but instead should be read as meaning “at least one”.

We claim:
 1. A fluid delivery device comprising: a housing configured tocontain a fluid reservoir; a needle configured to be in fluidcommunication with the fluid reservoir in an engaged position and out offluid communication with the fluid reservoir in an armed position and astorage position; a cap coupled to the housing and extending over aneedle button coupled to the needle in the storage position andpreventing the fluid delivery device from transitioning to the armed andengaged positions; a biasing member having a proximal end coupled to thehousing and a distal end configured to provide a force for the fluidreservoir; and a plunger coupled to the distal end of the biasingmember, the plunger being fixed with respect to the housing in thestorage position such that the biasing member does not provide the forceto the fluid reservoir and moveable with respect to the housing in thearmed position such that the biasing member provides the force to thefluid reservoir, wherein the cap includes a pin extending through thehousing and releaseably retaining the plunger in the storage positionsuch that removing the cap from covering the needle button releases theplunger from the housing and transitions the fluid delivery device fromthe storage position to the armed position.
 2. The fluid delivery deviceof claim 1, further comprising a hydraulic basal chamber coupled betweenthe biasing member and the fluid reservoir.
 3. The fluid delivery deviceof claim 2, further comprising a hydraulic pump chamber and a flowrestrictor fluidly coupling the hydraulic pump chamber and the hydraulicbasal chamber.
 4. The fluid delivery device of claim 2, wherein theplunger includes a plunger tip coupled to the hydraulic basal chamber.5. The fluid delivery device of claim 1, wherein the biasing membercomprises at least two overlapping coaxial springs.
 6. The fluiddelivery device of claim 1, wherein the plunger extends through thebiasing member.
 7. The fluid delivery device of claim 1, wherein theneedle is not moveable relative to the fluid reservoir in the storageposition and moveable relative to the fluid reservoir in the armedposition.
 8. The fluid delivery device of claim 1, wherein the housingcontains a fluid reservoir.
 9. The fluid delivery device of claim 1,wherein a delivery end of the needle is contained within the housing inthe storage and armed positions and extends from the housing in theengaged position.
 10. A fluid delivery device comprising: a housingconfigured to contain a fluid reservoir; a needle having a storageposition, an armed position, and an engaged position, the needleconfigured to be in fluid communication with the fluid reservoir in theengaged position and out of fluid communication with the fluid reservoirin the armed and storage positions; a biasing member having a proximalend and a distal end, the proximal end of the biasing member beingcoupled to the housing and the distal end of the biasing memberconfigured to provide a force for the fluid reservoir; and a plungercoupled to the distal end of the biasing member, the plunger being fixedwith respect to the housing in a locked position such that the biasingmember does not provide the force to the fluid reservoir and moveablewith respect to the housing in a released position such that the biasingmember provides the force to the fluid reservoir, wherein transitioningthe needle from the storage position to the armed position transitionsthe plunger from the locked position to the released position, whereinthe plunger is releaseably coupled to the housing with a pin extendingthrough the housing and a cap extends over the needle in the storageposition, the cap being coupled to the pin such that removing the capreleases the plunger from the housing.